United States. Bureau of Labor Statistics. "Nonfinancial Corporate Sector : Annual Data for 1981," Productivity and Costs (March 1, 1982). https://fraser.stlouisfed.org/title/131/item/55752, accessed on May 14, 2024.
United States. Bureau of Labor Statistics. "Nonfinancial Corporate Sector : Annual Data for 1981," Productivity and Costs (March 1, 1982). https://fraser.stlouisfed.org/title/131/item/55752, accessed on May 14, 2024.